BOGOR, Indonesia - Newborn baby Maryamah stared around from inside an incubator, her bright eyes swiveling left and right from under a woolen hat that was far too big for her.

When she was born prematurely, Maryamah was just 1.2 kilograms, less than half the usual weight of a newborn in Indonesia.

Now safely back at home, she is still diminutive but nestles comfortably in a small incubator lent to family, who live in a poor neighborhood in the city of Bogor on Java island.

She is one of hundreds of premature babies born in Indonesia benefiting from the work of an engineering professor who is building incubators and lending them for free to low-income families in a bid to fill a gap in the healthcare system.

"The government has a program of public health insurance, but it cannot cover all the people," said Raldi Artono Koestoer, who established the initiative.

Indonesia has the fifth greatest number of premature births of any nation in the world, at 675,700 a year, according to the World Health Organization. The WHO says that preterm birth complications are the leading cause of death among children under five.

Babies born early can need specialist care. Incubators keep them warm and can help prevent infections.

But getting access to the live-saving devices is a huge challenge for the millions living in poverty in Indonesia.

The public insurance scheme - introduced in 2014 - has helped as it sometimes covers the cost of incubators for a while.

But families unable to afford the high cost of continued care are often forced to take their newborns home early.

Koestoer, who works at the University of Indonesia just outside Jakarta, started his lending scheme back in 2012, using his technical expertise to design and build ultralight, portable incubators.

His interest in incubators began when he fixed one of the devices for his elder brother, a pediatrician, and then learned how to construct them himself.

To fund the scheme, he sought individuals willing to donate 3.5 million rupiah ($260) each - the cost of making one incubator - and also to transport the devices to the homes of selected families.

People requiring an incubator send a text message to a special number, and if they are deemed in need, a volunteer brings one round for them.

The service began in Jakarta, and has now expanded to an additional 48 cities. The professor has also recruited two of his students to work with him, and hopes to extend the initiative to 300 cities.

Koestoer, 62, says he has so far built 180 incubators that have helped about 1,500 babies, including twins and triplets.

Agence France - Presse